1. Field of the Invention
Replaceable Resilient Tire
2. Description of the Prior Art
In the past, it has been conventional on wheel chairs and other low velocity vehicles to use wired on tires, semi-pneumatic tires, and snap on tires containing a coil spring molded within the interior thereof. In the wired on tire, a length of wire surrounding or embedded in the tire rigidly secures the tire to the rim on which it is mounted. The replacement of a wired on tire by a user is extremely difficult, by the ordinary user, since special tools and a high degree of mechanical skill must be employed to remove the wired on tire from a rim and to install a new one in place thereof. Thus, the patient and or hospital must have a specially trained person capable of replacing and installing tires of this construction, or in lieu thereof incur the time and expense of sending the entire wheel chair back to the manufacturer for subsequent installation of one or both tires thereon.
To avoid the previously mentioned difficulties in installation or removal of wired on wheels, an alternative design known in the prior art as the semi-pneumatic tire has been used. This tire is a molded construction, which depends upon the strength and rigidity of the rubber to retain it on the wheel rim. However, this tire has proved to be unsatisfactory for numerous reasons. One reason is that the hard rubber used in the semi-pneumatic tire is not particularly resilient, and is very difficult to stretch in order to install the tire on the wheel rim or remove it therefrom. This lack of resiliency also may cause the tire to roll laterally from the rim, if the rubber is not sufficiently resilient to hold it in place thereon. A further disadvantage of the semi-pneumatic tire is that it is molded and is much heavier than an extruded tire.
Yet another operational disadvantage of the semi-pneumatic tire is that relatively hard rubber is employed to obtain the necessary strength therein, and this substantially reduces the cushioning effect that is expected from the tire.
The previously available snap on tire has a coil spring molded into the rubber, and as a result it is extremely difficult to place it on a rim, or remove it therefrom. The snap on tire, due to having a coil spring incorporated as a part thereof is much heavier, and is not as easily rollable as the tire of the present invention.
The primary purpose in devising the present invention is to provide a resilient tire for use on a wheel of a low velocity vehicle, and one that will be substantially free of the operational disadvantages of prior art tires used for this purpose.
A further object in devising the present invention is to provide a resilient tire that is easy to place on or remove from a rim, has good roll ability, has a good cushioning effect on the vehicle with which it is associated, can be fabricated from an extruded resilient material such as rubber containing compound or polymerized resin, and one that does not require special tools or special ability on the person that is to mount the tire on a rim or remove it therefrom.